The principal research objective of this study is to evaluate the effect of neonatal transportation of high-risk infants on mortality. To answer this question, the study design will produce a comparison of transported (versus) and a non-transported population of newborns, matched for hospital of birth, weight, gestational age and severity of condition using three different study sites, i.e., New York City, Illinois and Colorado. A multi-factorial design utilizing analysis of variance will be employed to detect significant differences in mean mortality rates (outcome measures) of the transported versus the non-transported populations and to test the pre-formulated sub-hypothesis.